[solved] QtSerialPort - Problem with waitForReadyRead() and bytesAvailable()
I can't get the functions waitForReadyRead() and bytesAvailable() to work as I expect them to.
I'm using Qt 4.7.4, Win 7, MinGW compiler.
QtSerialPort downloaded 11 Feb 2013.
The code in short is:
RS232Cmd = 0x1B; // 2 bytes, Esc A RS232Cmd = 'A'; serial->write(RS232Cmd,2); serial->waitForBytesWritten(100); bTest = serial->waitForReadyRead(5000); qDebug("w %d", bTest); temp_value = serial->bytesAvailable(); temp_value2 = serial->read(RS232Buffer, 8); qDebug("a %d", temp_value); qDebug("r %d", temp_value2); closeSerialPort(); }
The output I get is this:
First of all, with the 5000 parameter to waitForReadyRead(); I expect the program to wait 5 seconds before displaying the debug output if no data comes in, but there is no wait time that I can notice.
Second, I can see on the oscilloscope that the two bytes ('Esc' + 'A') are sent and that a 8 byte reply is received within 2ms.
Third, with a terminal program I can verify that the 8 byte reply is correctly received on the PC.
Any ideas on what's going wrong?
Or have I misunderstood the functionality of these functions?
Yes, it is a bug. Thx for posting.
Patch to fix it here: https://codereview.qt-project.org/#change,47729
You can wait and update repo after applied this patch,
or make changes yourself.
I changed line 161 in qserialport_win.cpp from:
and now my simplified example works.
Now, I can start working on the more complex software.
Please add [SOLVED] to caption